Not to completely piss in your cheerios, or even debate the point you're trying to make, you're mistaken when you say that the US maintains it's possession of Guantanamo Bay, Cuba through a 'legal loophole.'

The U.S. gained sovereignty over Guantanamo Bay as part of the Platt Amendment to the Cuban-American Treaty as a condition for the withdrawal of United States troops remaining in Cuba from the Spanish–American War. The treaty explicitly states that the United States has complete sovereignty over the area established in the treaty for the express purpose of a naval base, and Cuba itself retains ultimate sovereignty.

Furthermore, the U.S. leases Guantanamo Bay from Cuba, and continues to send lease payments (IIRC, ~4k/yr in 1934 Equivalent Dollars) to Cuba.The 1934 lease was made permanent by acceptance of the initial lease payment until such time that both governments agree to break the lease, or the U.S. abandons the naval base. To date, since the Cuban Revolution, only one of these rent checks has been cashed, with the rest left uncashed, though the U.S. continues to send a check annually.

Interesting, but I was referring to the legal loophole that exempts it from international law, yes?